Fiction
The Chronicles of Narnia (Books 1-6) by C. S. Lewis – Take my advice and stop before Book 7. Book 7 was infuriating, but the rest was actually a rather tolerable and enjoyable fantasy book. (I just looked for a link and it turns out I apparently hadn’t blogged about that evil mind-exploding trash that is Book 7. Done and done.)
The Twilight Series by Stephanie Meyer – You can see why I dislike this series in several posts on this site, so I won’t repeat those reasons here.
Unintentional Fiction
Beyond Belief: Strange, True Mysteries of the Unknown by Brad Steiger (1991). Example chapters: The Eerie Enigma of Ghost Ships, People Who Walk into the Past, Spooklights and Firedevils, The Terror of Spontaneous Human Combustion, and the rest (with equally appalling titles…if not more so). See my critique of the book in my seven part series.
skeptigirl 
And there’s always any book by David Icke, for those moments when despondency takes over, all life signs fail and you need a gloriously apoplectic shudder to kick start your joie de vivre. His writing makes me glad to be alive just so I can feel that I have at least one pure nutjob nemesis to push against. Children of the matrix is a particular repulsive favourite…